Objective:To studythe effectof matrineon proliferationof mouseskinfibroblastsinducedby platelet-derivedgrowthfactor-BB(PDGF-BB).Methods :MouseskinfibroblastswereobtainedfromnewbornI-CRmiceandpropagatedin vitro.Proliferationof cellwasanalyzedby mitochondrialreductionof tetrazoliumsalt MTT andactualcellcount.Re sults:Matrine(50to500μg/ml)causeddose-dependentreductionof serum-stimu-latedcellgrowth.Growthinhibitionwas totallyreversedafterremovalof the drug.Matrinealso inhibited PDGF-BBinducedcellgrowthdose-dependently.Conclusion:Matrineexhibitspotentanti-proliferationeffecton mouseskinfibroblast.Thiseffectappearsto be mediatedby decreaseof PDGF-inducedgrowth.Theseresultssug-gestthatmatrinemighthavepreventiveandtherapeuticimplicationin skinfibrosis.